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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Goodwill - Changes in the Net Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 28, 2020	Mar. 29, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Goodwill [Roll Forward]
Goodwill, beginning balance		$ 127.8		$ 127.8
Additions to Goodwill				19.9
Goodwill, Impairment Loss	$ 0.0	(147.7)	$ 0.0	(147.7)	$ 0.0
Goodwill, ending balance	0.0			0.0
Americas Staffing
Goodwill [Roll Forward]
Goodwill, beginning balance		58.5		58.5
Additions to Goodwill				19.9
Goodwill, Impairment Loss				(78.4)
Goodwill, ending balance	0.0			0.0
Global Talent Solutions
Goodwill [Roll Forward]
Goodwill, beginning balance		$ 69.3		69.3
Additions to Goodwill				0.0
Goodwill, Impairment Loss				(69.3)
Goodwill, ending balance	$ 0.0			$ 0.0